Driving printed circuit board for display device and display device having the same

ABSTRACT

An electronic device connection unit includes a substrate and a plurality of signal pads on the substrate configured to send signals from an electronic device to a driving printed circuit board (PCB). One or more active ground pads on the substrate are configured to connect at least the driving PCB to a reference voltage of the electronic device. One or more dummy ground pads on the substrate are configured to connect to the reference voltage of the electronic device without extending onto the driving PCB. One or more connectors are connected to the one or more dummy ground pads, where each of the one or more connectors is configured to electrically couple at least a subset of the one or more dummy ground pads to the one or more active ground pads.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit under 35 U.S.C. §119(a) of KoreanPatent Application No. 10-2014-0119081, filed on Sep. 5, 2014, which ishereby incorporated by reference for all purposes as if fully set forthherein.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to a driving printed circuit board for adisplay device and a display device having the driving printed circuitboard for a display device, and more particularly to a driving printedcircuit board (PCB) for connecting an electronic device for a displaydevice to a display panel, and a display device having the driving PCB.

2. Description of the Prior Art

With the development of the information society, various types ofrequirements for a display device for displaying an image are increasingand, recently, various display devices, such as a liquid crystal display(LCD), a plasma display panel (PDP), and an organic light emitting diodedisplay device (OLED), are being used.

An LCD includes an array substrate including a thin film transistor, anupper substrate including a color filter, a black matrix and/or thelike, and a liquid crystal material layer formed between the arraysubstrate and the upper substrate. The LCD is a device in which anarrangement state of a liquid crystal layer is controlled according toan electric field applied to both electrodes of a pixel area. Therefore,transmittance of light is controlled, and thus an image is displayed.

A display panel of the LCD is defined as an active area (AA), whichprovides an image to a user, and a non-active area (NA), which isadjacent to the AA. The display panel is commonly manufactured bycombining a first substrate with a second substrate. The first substrateis the array substrate, in which the pixel area is defined by theforming of the thin film transistor. The second substrate is the uppersubstrate, in which the black matrix and/or the color filter layer areformed.

The array substrate or the first substrate in which the thin filmtransistor is formed includes a plurality of gate lines (GLs) extendingin a first direction, and a plurality of data lines (DLs). One pixelarea (e.g., P) is defined by each gate line and each data line. In onepixel area (e.g., P), at least one thin film transistor may be formed,and a gate electrode or a source electrode of each thin film transistormay be connected to each gate line and data line.

In addition, in order to provide a gate signal and a data signalnecessary to drive each pixel to each gate line and data line, a gatedriving unit (i.e., a gate driving circuit), a data driving circuit orthe like is formed in the NA or outside of the panel.

Among these, the gate driving circuit may be formed on the NA of thedisplay panel in a process of forming various signal lines and a pixelof the display panel. Thus, the gate driving circuit may be implementedas a gate in panel (GIP) type in which the gate driving circuit isincluded in the panel. However, the gate driving circuit and the datadriving circuit may be included in the same driver IC and may beseparately disposed under the display panel.

Meanwhile, the display panel including the data driving circuit (i.e.,D-IC) may be expressed as a liquid crystal monitor. The liquid crystalmonitor is connected to a customer system such as a mobile phone, a PC,or a tablet PC, receives a data signal from the customer system, and isoperated as a display device for the customer system.

In addition, a driving printed circuit board, which is connected to theliquid crystal monitor to provide various signals to the gate drivingcircuit and the data driving circuit included in the liquid crystalmonitor, is provided. Various driving elements including a timingcontroller are mounted on the driving printed circuit board. One end ofthe driving printed circuit board (PCB) is coupled to the liquid crystalmonitor through a flexible printed circuit board (FPC) or a flexiblecircuit film, and another end of the driving PCB is connected to aconnection unit of the customer system through a connector (i.e., CNT)unit in which various terminals or pads are formed.

Meanwhile, in order to provide an electrical stability of various signallines formed in a main circuit unit of the driving PCB, at least onedummy ground pad may be formed in the connector (i.e., CNT) unit of thedriving PCB for the customer system. Some of the ground pads may not beelectrically connected to a ground, and may be floated.

As described above, the ground pad floated in the connector (i.e., CNT)unit of the driving PCB for the customer system may possess a staticelectricity or an external inflow charge, and then the staticelectricity or the external inflow charge may flow into the liquidcrystal monitor while connecting the driving PCB with the customersystem. Thus, the ground pad may bring about various defects to theliquid crystal monitor.

SUMMARY OF THE DISCLOSURE

An electronic device connection unit is provided. In one embodiment, theelectronic device connection unit includes a substrate. A plurality ofsignals pads on the substrate are configured to send signals from anelectronic device to a driving printed circuit board (PCB). One or moreactive ground pads on the substrate are configured to connect at leastthe driving PCB to a reference voltage of the electronic device. One ormore dummy ground pads are disposed on the substrate without extendingonto the driving PCB. The one or more dummy ground pads are configuredto connect to the reference voltage of the electronic device. One ormore connectors are connected to the one or more dummy ground pads,where each of the one or more connectors is configured to electronicallycouple at least a subset of the one or more dummy ground pads to the oneor more active ground pads.

A driving printed circuit board (PCB) coupling a display panel to anelectronic device is also provided. The driving PCB includes a substrateand a plurality of signal lines disposed on the substrate. The signallines are configured to receive signals from the electronic device fordriving the display panel. The driving PCB also includes one or moreground metal patterns on the substrate, and applies a reference voltageto the one or more ground metal patterns. An electronic deviceconnection unit of the driving PCB is configured to connect the drivingPCB to the electronic device. The electronic device connection unitincludes a plurality of signal pads on the substrate and coupled to thesignal lines of the driving PCB. The signal pads are configured to sendsignals from the electronic device to the driving PCB. One or moreactive ground pads on the substrate are coupled to the ground metalpatterns of the driving PCB, where the one or more active ground padsare configured to connect at least the driving PCB to a referencevoltage of the electronic device. One or more dummy ground pads of theelectronic device connection unit, disposed on the substrate withoutextending onto the driving PCB, are configured to connect to thereference voltage of the electronic device. One or more connectors areconnected to the one or more dummy ground pads. Each of the one or moreconnectors is configured to electrically couple at least a subset of theone or more dummy ground pads to the one or more active ground pads.

An electronic device connection unit is also provided. The electronicdevice connection unit includes a substrate and a plurality of signalpads on the substrate. The signal pads are configured to send signalsfrom an electronic device to a driving printed circuit board (PCB). Oneor more active ground pads on the substrate are configured to connect atleast the driving PCB to a reference voltage of the electronic device.One or more dummy ground pads are disposed on the substrate withoutextending onto the driving PCB. The one or more dummy ground pads areconfigured to connect to the reference voltage of the electronic device.One or more connectors are connected to the dummy ground pads. Each ofthe connectors is configured to electrically couple at least a subset ofthe one or more dummy ground pads to the one or more active ground pads.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentdisclosure will be more apparent from the following detailed descriptiontaken in conjunction with the accompanying drawings, in which:

FIGS. 1A and 1B are configuration diagrams of a display device includinga display panel, a customer system and a driving printed circuit boardwhich connects the display panel to the customer system;

FIGS. 2 and 3 are views for a customer system connector unit of adriving PCB applied to an embodiment of the present disclosure, FIG. 2is an enlarged plan view of the customer system connector unit, and FIG.3 is an equivalent circuit diagram for the customer system connector;

FIG. 4 is an enlarged plan view of the customer system connector unit ofthe driving PCB according to an embodiment of the present disclosure;

FIG. 5 is an enlarged plan view of a customer system connector unit of adriving PCB according to another embodiment of the present disclosure;and

FIG. 6 is an enlarged plan view of a customer system connector unit of adriving PCB according to another embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be describedwith reference to the accompanying drawings. In designating elements ofthe drawings by reference numerals, the same elements will be designatedby the same reference numerals although they are shown in differentdrawings. Further, in the following description of the presentdisclosure, a detailed description of known functions and configurationsincorporated herein will be omitted when it may make the subject matterof the present disclosure rather unclear.

Furthermore, in the description of the structural elements of thepresent disclosure, terms of “first”, “second”, “A”, “B”, “(a)”, “(b)”and the like may be used. Each of these terminologies is not used todefine an essence, order or sequence of a corresponding component butused merely to distinguish the corresponding component from othercomponent(s). In the case that it is described that a certain structuralelement “is connected to”, “is coupled to”, or “is in contact with”another structural element, it should be interpreted that anotherstructural element may “be connected to”, “be coupled to”, or “be incontact with” the structural elements as well as that the certainstructural element is directly connected to or is in direct contact withanother structural element.

FIGS. 1A and 1B are configuration diagrams of a display device includinga display panel, a customer system and a driving printed circuit boardwhich connects the display panel to the customer system.

A detailed configuration diagram of a display device to which anembodiment of the present disclosure may be applied may include adisplay panel 110, a customer system 120 such as a user terminal, a testdevice, or the like, and a driving printed circuit board (PCB) 200.Here, the driving PCB 200 may connect the display panel with thecustomer system, and may include a connector unit connected to thecustomer system. In addition, various driving elements of a displaydevice may be mounted on the driving PCB 200.

The display panel 110 may be a liquid crystal display panel, but is notlimited thereto. That is, the display panel 110 may be another type ofdisplay panel such as an organic light emitting diode (OLED) displaydevice, a plasma display panel (PDP) and the like.

That is, a type of a display panel which may be connected to the drivingPCB 200 according to an embodiment of the present disclosure is notlimited to a specific type.

But, for convenience of understanding, hereinafter, the display panelaccording to an embodiment of the present disclosure is regarded as theliquid crystal display panel.

The liquid crystal display panel which is the display panel 110 includesan array substrate as a lower substrate, a color filter substrate as anupper substrate, and a liquid crystal layer injected between the arraysubstrate and the color filter substrate. The array substrate includes aplurality of gate lines, a plurality of data lines, and a plurality ofthin film transistors. The color filter substrate includes a colorfilter and a black matrix.

A plurality of pixels P which are defined as crossing areas of the gatelines GL and the data lines DL are formed in the display panel 110. Thatis, in the lower array substrate, the data lines and the gate linescross, and the pixels including m*n (each of m and n is a positiveinteger) liquid crystal cells (i.e., Clc) are formed in a matrix type.In the display panel 110, k (k is a positive integer) dummy lines (notshown) may be further formed.

Each liquid crystal cell (i.e., Clc) includes a thin film transistor(TFT), a pixel electrode connected to the TFT, a storage capacitor Cst,and the like. The liquid crystal cell (Clc) is driven by a voltagedifference between a pixel electrode and a common electrode, adjuststransmittance of incident light, and thus implements a display imagecorresponding to an image data. Here, the pixel electrode charges a datavoltage through the TFT, and the common electrode receives a commonvoltage (i.e., Vcom).

The black matrix, the color filter and the common electrode are formedon an upper glass substrate of the display panel 110. The commonelectrode is formed on the upper glass substrate in a vertical electricfield driving method such as a TN mode and a VA mode. The commonelectrode may be formed on a lower glass substrate together with thepixel electrode in a horizontal electric field driving method such as anIPS mode or an FFS mode.

A gate driving circuit 112 for providing a gate output signal (i.e.,Vout) to a gate line may be directly formed on the lower substrate ofthe display panel through a TFT array process according to a gate inpanel (GIP) method.

That is, the gate driving circuit 112 may be formed in the non-activearea (NAA) outside the active area (AA) of the display panel 110, andmay be symmetrically formed at left and right sides (or upper and lowersides) of the panel, but is not limited thereto.

The driving PCB 200 is a printed circuit board including a drivingelement such as a timing controller (i.e., T-CON) and a data drivingcircuit (i.e., D-IC). The driving PCB 200 may include a main substratearea 210 on which the driving element and various signal lines areformed, and a connector unit disposed at both sides of the mainsubstrate area 210.

The connector unit may include a display panel connection unit 220 and acustomer system connector unit 230. The display panel connection unit220 is for connecting the driving PCB 200 to the display panel 110through a flexible PCB (FPCB), a tape carrier package (TCP) or the likeat one end of the driving PCB 200. The customer system connector unit230 is for connecting the driving PCB 200 to a customer system such as auser terminal or test equipment.

The driving PCB 200 may be manufactured as a type of the FPCB. In theabove, the driving PCB 200 includes the timing controller (i.e., T-CON),the data driving circuit (i.e., D-IC), and the like, but is not limitedthereto.

That is, in an embodiment shown in FIG. 1A, the driving circuit may benot included in the display panel 110, and all driving circuit elementssuch as the timing controller, the gate driving circuit and the datadriving circuit may be mounted on the driving PCB 200 which connects thedisplay panel with the customer system 120.

In addition, in an embodiment shown in FIG. 1B, the display panel 110may be a display panel of a chip on glass (COG) or a gate in panel (GIP)structure in which the gate driving circuit element is directly formedin the NA disposed at one side of the display panel 110.

In the embodiment of FIG. 1B, the gate driving circuit 112 may be formedin the display panel 110 and the data driving circuit (i.e., D-IC) 114may be mounted in the display panel or a separate FPCB. Thus, in thedriving PCB 200 defined in an embodiment of the present disclosure, thegate driving circuit or the data driving circuit may not be included,and other driving elements necessary to drive the display panel may beincluded.

As described above, the driving PCB 200 included in an embodiment of thepresent disclosure should be understood as a concept including all typesof PCB, printed circuit film or the like, which include at least oneelement necessary to drive the display panel and is for connecting thedisplay panel 110 or the liquid crystal monitor (LCM) to the customersystem.

But, the driving PCB 200 includes the customer system connector unit 230to be connected to the connection unit of the customer system 120, inaddition to the main substrate area 210 in which the driving element andthe like are disposed.

The customer system connector unit 230 of the driving PCB 200 mayinclude a signal pad and a ground pad. Here, the signal pad is formed atan end portion of a plurality of signal lines extending from the mainsubstrate area 210. The ground pad extends from a ground pattern formedin the main substrate area. In addition, the customer system connectorunit 230 of the driving PCB 200 may include a plurality of dummy groundpads. When the customer system connector unit 230 of the driving PCB 200is connected to the customer system, a ground signal is applied to theplurality of dummy ground pads, and the plurality of dummy ground padsare floated when considering only the driving PCB 200.

When the dummy ground pad is connected to the customer system, since thedummy ground pad electrically receives a ground signal, the dummy groundpad may play a role of increasing an electrical stability of varioussignal lines, especially a pair of signal lines. However, when the dummyground pad is not connected to the customer system, an external chargedue to an electrostatic discharge (ESD), an electrical overstress (EOS)or the like may be stored in the dummy ground pad, and then the externalcharge may flow into an adjacent pad. Thus, the dummy ground pad maybring about electrical damage to the display panel.

In the present disclosure, a driving PCB is provided for connecting adisplay panel and a customer system. The driving PCB includes a mainsubstrate area including at least one display panel driving element, anda customer system connector unit formed at one end of the main substratearea and connected to a connection unit of the customer system. Thecustomer system connector unit includes at least one dummy ground pad,and a connection line electrically connecting at least one of dummyground pads to an adjacent ground pad.

Hereinafter, an embodiment of the present disclosure will be describedin detail with reference to FIGS. 2 to 5.

FIGS. 2 and 3 are views for a customer system connector unit of adriving PCB. FIG. 2 is an enlarged plan view of the customer systemconnector unit, and FIG. 3 is an equivalent circuit diagram for thecustomer system connector.

As shown in FIGS. 2 and 3, in the main substrate area 210, a pluralityof signal lines 310 and 320 are formed. In the customer system connectorunit 230, a plurality of signal pads 360 are extended from the signallines and formed in an end portion of the signal lines.

In addition, a plurality of ground metal patterns 330 are formed in themain substrate area 210, and a ground signal is applied to the groundmetal pattern in the driving PCB. Meanwhile, a ground pad 370 directlyextending from the ground metal pattern 330 is formed in the customersystem connector unit 230.

Meanwhile, the signal lines may include, for example, a single signalline 310 such as a high potential voltage signal (e.g., VDD), and a pairof signal lines 320 and 320′ for providing a pair of differentialsignals.

The pair of signal lines 320 and 320′ may be, for example, signal linesfor providing a DO negative (DON) and a DO positive (DOP) signals,signal lines for providing a clock negative (CLKN) and a clock positive(CLKP) signals, or the like.

In one embodiment, the pair of signal lines are adjacently disposed soas to maximize a transmission characteristic, as a circuit type recentlyused often to change a parallel structure to a serial structure.

In addition, when the differential signal is provided through the pairof signal lines, electromagnetic Interference (EMI) is reduced byproviding a ground signal to an adjacent area of the pair signal line toform a balanced electromagnetic field (EMF).

To this end, as shown in FIGS. 2 and 3, a plurality of the pair ofsignal lines 320 and 320′ are formed in the main substrate area of thedriving PCB 200, and a pair of signal pads 322 and 322′ are formed atthe end portions of each of the plurality of the pairs of signal lines320 and 320′. Corresponding signals are applied to the pair of signalpads 322 from the customer system, and the signals are applied to thedriving PCB 200 and the display panel 110 along the pair of signal lines320 and 320′.

Meanwhile, as described above, a dummy ground pad 380 is formed betweena pair of signal pads 322 and 322′ for an electrical stability of thepair of signal lines. When the driving PCB 200 is connected to thecustomer system 120, since the ground signal is applied to the dummyground pad from the customer system, the dummy ground pad secures theelectrical stability of the pair of signal pads or the differentialsignal applied to the pair of signal pads.

In addition, at least one other dummy ground pad may be formed between apair of signal pads and adjacent to another pair of signal pads.

In the present specification, the dummy ground pad formed between a pairof signal pads 320 and 320′ is distinguished and described as a firstdummy ground pad 380, and two dummy ground pads disposed betweenadjacent pairs of signal pads are distinguished and described as asecond dummy ground pad 390.

When the first dummy ground pad 380 and the second dummy ground pad 390are connected to the customer system, the first dummy ground pad 380 andthe second dummy ground pad 380 receive the ground signal from thecustomer system, and thus improve the electrical stability of the pairof signal lines and the like. However, before the first dummy ground pad380 and the second dummy ground pad 390 are connected to the customersystem, the first dummy ground pad 380 and the second dummy ground pad390 are electrically floated based on the driving PCB.

In FIG. 2, for the convenience of description, the single signal pad 360and the pair of signal pads 322 which are signal pads to which varioussignals are applied are shown in white without a shadow, the groundmetal pattern 330 formed in the main substrate and the ground pad 370directly extending from the ground metal pattern 330 are shown as adeviant crease line shadow, and the first dummy ground pad 380 and thesecond dummy ground pad 390 are shown as a gray area.

The first dummy ground pad 380 and the second dummy ground pad 390 aremetal patterns electrically floated before the first dummy ground pad380 and the second dummy ground pad 390 are connected to the customersystem. Therefore, the first dummy ground pad 380 and the second dummyground pad 390 may possess a static charge or other abnormal chargesgenerated in the outside, and then the abnormal external chargespossessed in the first dummy ground pad 380 and the second dummy groundpad 390 may flow into an adjacent pad and the like. Thus, the abnormalexternal charge may damage elements in the driving PCB or the displaypanel.

Thus, in an embodiment of the present disclosure, the dummy ground padformed in the customer system connector unit of the driving PCBconnecting the display panel to the customer system is coupled to anadjacent ground pad to resolve the above-mentioned problems.

FIG. 4 is an enlarged plan view of the customer system connector unit230 of the driving PCB according to an embodiment of the presentdisclosure.

As shown in FIGS. 1A and 1B, the driving PCB by an embodiment of thepresent disclosure is provided to connect the display panel 110 to thecustomer system 120. The driving PCB includes the main substrate area210 including at least one display panel driving element, and thecustomer system connector unit 230 formed at one end of the mainsubstrate area and connected to a connection unit of the customersystem. The customer system connector unit 230 includes at least onedummy ground pad, and at least one of the dummy ground pads iselectrically connected to an adjacent ground pad through a connectionline.

More specifically, as shown in FIG. 4, at least one single signal line310 and at least one pair of signal lines 320 and 320′ are formed in themain substrate area 210, and at least one ground metal pattern 330 isformed between signal lines.

In addition, in the customer system connector unit 230 of the drivingPCB 200, the pair of signal pads 322 and 322′ extending from the pair ofsignal lines are formed, the first dummy ground pad 380 disposed betweenthe two signal pads included in a pair of signal pads is formed, and twosecond dummy ground pads 390 are formed between adjacent pairs of signalpads, i.e between one pair of signal pads and adjacent to another pairof signal pads. In addition, the ground pad 370 directly extending fromthe ground metal pattern 330 of the main substrate area is also formedin the customer system connector unit 230 of the driving PCB 200.

In the embodiment of FIG. 4, the second dummy ground pad 390 iselectrically connected to the ground metal pattern 330 disposed on themain substrate area through an additional connection line 420, and thefirst dummy ground pad 380 is connected to the adjacent second dummyground pad 390 through the connection line 410.

That is, in the embodiment of FIG. 4, since the second dummy ground pad390 connected to the ground metal pattern 330 through the additionalconnection line 420 performs as a type of ground pad function and thefirst dummy ground pad disposed between two signal pads 322 and 322′included in the pair of signal pads is connected to the ground padthrough the connection line 410, the first and second dummy ground padsare taken out of a floating state.

As described above, according to the embodiment of FIG. 4, since both ofthe first and second dummy ground pads 380 and 390 are electricallyconnected to the ground metal pattern to which the ground signal isapplied in the driving PCB 200, the first and second dummy ground pads380 and 390 are taken out of the floating state. Therefore, although thedriving PCB 200 is not connected to the customer system, damage of thedisplay panel or the driving circuit unit from the external electricalshock such as ESD or EOS may be prevented.

That is, as described in the embodiment of FIG. 4, the dummy ground padis electrically grounded even when the driving PCB 200 is not connectedto the customer system 120. Therefore, although the dummy ground pad mayaccumulate abnormal charge when the driving PCB 200 is not connected tothe customer system 120, the connections to the ground metal patterns ofthe driving PCB 200 dissipate the abnormal charge from the dummy groundpads to reduce damage to the driving PCB 200.

FIG. 5 is an enlarged plan view of a customer system connector unit 230of a driving PCB 200 according to another embodiment of the presentdisclosure.

The embodiment of FIG. 5 has a similar configuration to the embodimentof FIG. 4, and only a position where an additional connection line 420′is formed is different from that of the embodiment of FIG. 4.

That is, in the embodiment of FIG. 4, the additional connection line 420for electrically connecting the second dummy ground pads 390, which aretwo dummy ground pads disposed between the adjacent pairs of signal pads322 and 322′, to the ground connects the second dummy ground pads 390directly to the ground metal pattern 330 of the driving PCB.

In contrast, in the embodiment of FIG. 5, since the second dummy groundpad 390 is directly connected to the ground pad 370 rather than theground metal pattern 330 through the additional connection line 420′extending in a horizontal direction, the embodiment of FIG. 5 isdifferentiated from the embodiment of FIG. 4.

In the embodiment of FIG. 5 as well, similar to the embodiment of FIG.4, since both of the first and second dummy ground pads 380 and 390 areelectrically coupled to the ground metal pattern to which the groundsignal is applied in the driving PCB 200, even though the driving PCB isnot connected to the customer system, the electrical damage of thedisplay panel and the like from external electrical shock may beprevented.

FIG. 6 is an enlarged plan view of a customer system connector unit 230of a driving PCB 200 according to another embodiment of the presentdisclosure.

Differently from the embodiments of FIGS. 4 and 5, in which the firstdummy ground pad 380 is connected to only the second dummy ground pad390 adjacent to the first dummy ground pad 380, in an embodiment of FIG.6, the first dummy ground pad 380, which is disposed between the twosignal pads 322 and 322′ included in a pair of signal pads and isfloated, is directly connected to the ground pad 370 adjacent to thefirst dummy ground pad 380.

That is, in the embodiment of FIG. 6, the customer system connector unitmay include a first connection line 630 for directly connecting thefirst dummy ground pad 380 to the ground pad 370 adjacent to the firstdummy ground pad 380, and a second connection line 610 connecting thefirst dummy ground pad 380 to the second dummy ground pad 390electrically connected to the ground metal pattern 330 through theadditional connection line 420.

Summarizing the configurations by the above-mentioned variousembodiments of the present disclosure, the customer system connectorunit 230 of the driving PCB 200 connecting the display panel 110 to thecustomer system 120 includes at least one floated dummy ground pad, andthe dummy ground pads are each electrically coupled to an adjacentground pad through connection lines.

At this time, the dummy ground pad is the first dummy ground pad 380disposed between the pair of signal pads 322 and 322′ respectivelyattached to the corresponding end of the pair of signal lines formed inthe main substrate area 210 of the driving PCB 200. The above-mentionedground pad may be the first ground pad 370 directly extending from theground metal pattern 330, which is formed in the main substrate area,and may be the adjacent second dummy ground pad 390 electrically coupledto the ground metal pattern 330 or the first ground pad 370 through theadditional line.

That is, since the second dummy ground pad 390 is disposed between atleast two pairs of signal pads, and is connected to the ground metalpattern 330 or the first ground pad 370 through the additionalconnection lines 420 and 420′, the second dummy ground pad 390 acts as atype of a ground pad.

At this time, the connection line for electrically coupling the firstdummy ground pad 380 to a ground area may include a first connectionline 630 directly connecting the first dummy ground pad 380 to the firstground pad 370, and a second connection line 610 connecting the firstdummy ground pad 380 to the second dummy ground pad 390 adjacent to thefirst dummy ground pad 380, in this case, the second dummy ground pad iselectrically coupled to the ground metal pattern through the additionalconnection line.

The dummy ground pads 380 and 390 defined in embodiments of the presentdisclosure should be understood as all pads to which the ground signalis electrically applied in order to provide the electrical stability ofthe pair of signal lines and the like when the driving PCB 200 isconnected to the customer system 120, and which are floated when thedriving PCB 200 is not connected to the customer system 120.

When the embodiment described above is used, since the plurality ofdummy ground pads which are floated in order to provide the electricalstability when the driving PCB is connected to the customer system areincluded in the connector unit of the driving PCB, and the plurality ofdummy ground pads are electrically coupled to the ground area, theplurality of dummy ground pads are taken out of the floating state.Therefore, even in the state in which the driving PCB is not connectedto the customer system, the damage of the display panel or the drivingcircuit unit from the external electrical shock such as ESD, EOS, andthe like may be prevented.

Thus, electrical strength of the connector unit of the driving PCBconnecting the display panel or the LCM to the customer system such asthe user terminal, the test equipment or the like may be improved.Therefore, the display panel and the like may be protected from theexternal abnormal charge.

The above description and the accompanying drawings provide an exampleof the technical idea of the present disclosure for illustrativepurposes only. Those having ordinary knowledge in the technical field,to which the present disclosure pertains, will appreciate that variousmodifications and changes in form, such as combination, separation,substitution, and change of a configuration, are possible withoutdeparting from the essential features of the present disclosure.Accordingly, the embodiments disclosed in the present disclosure aremerely to not limit but describe the technical spirit of the presentdisclosure. Further, the scope of the technical spirit of the presentdisclosure is limited by the embodiments. The scope of the presentinvention shall be construed on the basis of the accompanying claims insuch a manner that all of the technical ideas included within the scopeequivalent to the claims belong to the present disclosure.

What is claimed is:
 1. A display device, comprising: a display panel; adriving printed circuit board (PCB) configured to drive the displaypanel based on inputs received from an electronic device; and anelectronic device connection unit configured to connect the driving PCBto the electronic device, the electronic device connection unitcomprising: a substrate, a plurality of signal pads on the substrate andconfigured to send signals from the electronic device to the drivingPCB, one or more active ground pads on the substrate and configured toconnect at least the driving PCB to a reference voltage of theelectronic device, one or more dummy ground pads on the substrate andconfigured to connect to the reference voltage of the electronic devicewithout extending onto the driving PCB, and one or more connectorsconnected to the one or more dummy ground pads, each of the one or moreconnectors configured to electrically couple at least a subset of theone or more dummy ground pads to the one or more active ground pads. 2.The display device of claim 1, wherein the driving PCB furthercomprises: one or more ground metal patterns, the one or more groundmetal patterns coupled to the one or more active ground pads andsupplying the reference voltage from the driving PCB to the ground pad.3. The display device of claim 2, wherein the plurality of signal padscomprise one or more pairs of signal pads, each pair of signal padsconfigured to receive a differential signal from the electronic device,and wherein the one or more dummy ground pads comprise: a first dummyground pad disposed on the substrate between a pair of the signal pads;and a second dummy ground pad disposed on the substrate adjacent to thepair of signal pads; wherein the one or more connectors connect thefirst dummy ground pad to the second dummy ground pad and the seconddummy ground pad to the one or more ground metal patterns.
 4. Thedisplay device of claim 2, wherein the plurality of signal pads compriseone or more pairs of signal pads, each pair of signal pads configured toreceive a differential signal from the electronic device, and whereinthe one or more dummy ground pads comprise: a first dummy ground paddisposed on the substrate between a pair of the signal pads; and asecond dummy ground pad disposed on the substrate adjacent to the pairof signal pads; wherein the one or more connectors connect the firstdummy ground pad to the second dummy ground pad, the first dummy groundpad to the one or more active ground pads, and the second dummy groundpad to the one or more ground metal patterns.
 5. The display device ofclaim 1, wherein the plurality of signal pads comprise one or more pairsof signal pads, each pair of signal pads receiving a differential signalfrom the electronic device, and wherein the one or more dummy groundpads comprise: a first dummy ground pad disposed on the substratebetween a pair of the signal pads; and a second dummy ground paddisposed on the substrate adjacent to the pair of signal pads; whereinthe one or more connectors connect the first dummy ground pad to thesecond dummy ground pad and the second dummy ground pad to the at leastone or more active ground pads.
 6. The display device of claim 5,wherein the second dummy ground pad is adjacent to one of the activeground pads and wherein one of the connectors is configured to connectto the second dummy ground pad to the adjacent active ground pad.
 7. Thedisplay device of claim 1, wherein the plurality of signal pads compriseone or more pairs of signal pads, each pair of signal pads receiving adifferential signal from the electronic device, and wherein the one ormore dummy ground pads comprise: a first dummy ground pad disposedbetween a pair of the signal pads; and a second dummy ground padadjacent to the pair of signal pads; wherein the one or more connectorsconnect the first dummy ground pad to the second dummy ground pad andthe first dummy ground pad to the one or more active ground pads.
 8. Thedisplay device of claim 1, wherein the driving PCB includes theelectronic device connection unit on a first side and a display panelconnection unit on a second side, the display panel connection unitincluding one or more display panel driving units configured to drivethe display panel in response to the signals received from theelectronic device.
 9. The display device of claim 1, wherein the drivingPCB comprises a plurality of signal lines, each signal line coupled to asignal pad in the electronic device connection unit and configured toreceive the signals from the electronic device.
 10. A driving printedcircuit board (PCB) coupling a display panel to an electronic device,the driving PCB comprising: a substrate; a plurality of signal linesdisposed on the substrate, the signal lines configured to receivesignals from the electronic device for driving the display panel; one ormore ground metal patterns on the substrate, the driving PCB applying areference voltage to the one or more ground metal patterns; and anelectronic device connection unit configured to connect the driving PCBto the electronic device, the electronic device connection unitcomprising: a plurality of signal pads on the substrate and coupled tothe signal lines, the signal pads configured to send signals from theelectronic device to the driving PCB, one or more active ground pads onthe substrate and coupled to the ground metal patterns, the one or moreactive ground pad configured to connect at least the driving PCB to areference voltage of the electronic device, one or more dummy groundpads disposed on the substrate without extending onto the driving PCB,the one or more dummy ground pads configured to connect to the referencevoltage of the electronic device, and one or more connectors connectedto the one or more dummy ground pads, each of the one or more connectorsconfigured to electrically couple at least a subset of the one or moredummy ground pads to the one or more active ground pads.
 11. The drivingPCB of claim 10, wherein the plurality of signal pads comprise one ormore pairs of signal pads, each pair of signal pads receiving adifferential signal from the electronic device, and wherein the one ormore dummy ground pads comprise: a first dummy ground pad disposedbetween a pair of the signal pads; and a second dummy ground padadjacent to the pair of signal pads; wherein the one or more connectorsconnect the first dummy ground pad to the second dummy ground pad andthe second dummy ground pad to the one or more ground metal patterns.12. The driving PCB of claim 10, wherein the plurality of signal padscomprise one or more pairs of signal pads, each pair of signal padsreceiving a differential signal from the electronic device, and whereinthe one or more dummy ground pads comprise: a first dummy ground paddisposed between a pair of the signal pads; and a second dummy groundpad adjacent to the pair of signal pads; wherein the one or moreconnectors connect the first dummy ground pad to the second dummy groundpad and the first dummy ground pad to the one or more ground metalpatterns.
 13. The driving PCB of claim 10, wherein the plurality ofsignal pads comprise one or more pairs of signal pads, each pair ofsignal pads receiving a differential signal from the electronic device,and wherein the one or more dummy ground pads comprise: a first dummyground pad disposed between a pair of the signal pads; and a seconddummy ground pad adjacent to the pair of signal pads; wherein the one ormore connectors connect the first dummy ground pad to the second dummyground pad and the second dummy ground pad to the one or more activeground pads.
 14. The driving PCB of claim 13, wherein the second dummyground pad is adjacent to one of the active ground pads and wherein oneof the connectors is configured to connect to the second dummy groundpad to the adjacent active ground pad.
 15. The driving PCB of claim 10,wherein the plurality of signal pads comprise one or more pairs ofsignal pads, each pair of signal pads receiving a differential signalfrom the electronic device, and wherein the one or more dummy groundpads comprise: a first dummy ground pad disposed between a pair of thesignal pads; and a second dummy ground pad adjacent to the pair ofsignal pads; wherein the one or more connectors connect the first dummyground pad to the second dummy ground pad and the first dummy ground padto the one or more active ground pads.
 16. The driving PCB of claim 10,wherein the driving PCB includes the electronic device connection uniton a first side and a display panel connection unit on a second side,the display panel connection unit including one or more display paneldriving units driving the display panel in response to the signalsreceived from the electronic device.
 17. An electronic device connectionunit comprising: a substrate; a plurality of signal pads on thesubstrate, the signal pads configured to send signals from an electronicdevice to a driving printed circuit board (PCB); one or more activeground pads on the substrate, the one or more active ground padconfigured to connect at least the driving PCB to a reference voltage ofthe electronic device; one or more dummy ground pads disposed on thesubstrate without extending onto the driving PCB, the one or more dummyground pads configured to connect to the reference voltage of theelectronic device; and one or more connectors connected to the one ormore dummy ground pads, each of the one or more connectors configured toelectrically couple at least a subset of the one or more dummy groundpads to the one or more active ground pads.
 18. The electronicconnection unit of claim 17, wherein the driving PCB is configured todrive a display panel based on inputs received from the electronicdevice.
 19. The electronic connection unit of claim 17, wherein theelectronic device supplies the reference voltage.